The 2016 update incorporates many significant changes (Acta Neuropathol 2016;131:803), most importantly the definition of new entities based on molecular characteristics for the first time, and the endorsement of the use of "integrated" diagnosis that incorporate phenotypic and genotypic information in a layered format (Brain Pathol 2014;24:429)

Gliomas are entirely restructured; astrocytomas and oligodendrogliomas are now under the same category ("diffuse astrocytic and oligodendroglial tumors"), which are further defined by the presence or absence of IDH mutations fundamentally

Medulloblastomas are restructured with incorporation of molecularly defined entities that determine prognostic categories

NOS (not otherwise specified): terminology to be used when molecular information is insufficient, either because testing cannot be fully performed or the results don’t fit within a defined category

New entities have been added, such as diffuse midline glioma, H3 K27M mutant, diffuse leptomeningeal glioneuronal tumor and epithelioid glioblastoma

Some entities, variants and patterns have been deleted, such as gliomatosis cerebri (now considered a pattern instead of an entity) and "Primitive neuroectodermal tumor" (PNET) terminology for embryonal tumors

Brain invasion is added as a criterion for atypical meningioma, WHO grade II

Solitary fibrous tumor and hemangiopericytoma are now considered a combined diagnosis (solitary fibrous tumor / hemangiopericytoma)

They are graded 1 - 3 using a soft tissue type grading system

This represents the first time that grading of CNS tumors is applied within a single entity - typically each entity is assigned a single WHO grade

Nerve sheath tumors are expanded, with incorporation of hybrid nerve sheath tumor and separation of melanotic schwannoma from others

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